Problem: Add. $25.8 + 54 =$
Explanation: There are many ways to solve this problem. Let's see two ways we can solve it. Place value table Let's line up the numbers by their decimal places. Tens Ones $.$ Tenths $2$ ${5}$ $.$ ${8}$ $5$ $4$ $.$ ${0}$ Because ${54}$ is a whole number, we can add a decimal point and a $0$ behind to make the columns align. Now, let's add each place value column. Tens Ones $.$ Tenths $2$ ${5}$ $.$ ${8}$ $+$ $5$ ${4}$ $.$ ${0}$ $\underline{~~~~}$ $\underline{~~~~}$ $\underline{~~~~}$ $\underline{~~~~}$ $7$ $9$ $.$ $8$ Decomposing the numbers We can group the whole numbers together and the decimals together. $\begin{aligned} &({25} + {54}) + {0.8}\\\\ &=79 + {0.8}\\\\ &=79.8 \end{aligned}$ $25.8 + 54=79.8$